ABSTRACT
A special purpose gamma-ray computed tomography scanner has been developed for the precise measurement of bone density in the distal forearm. Details of the scanner hardware and computer analysis technique are given. Suitable phantoms have been used to test the operation of the scanner, which has been used to measure trabecular and cortical bone density with a precision better than 1%.
Subject(s)
Bone and Bones/diagnostic imaging , Densitometry/instrumentation , Tomography, X-Ray Computed/instrumentation , Biomedical Engineering , Gamma Rays , HumansSubject(s)
Pacemaker, Artificial/standards , Data Collection , Humans , Microcomputers , Time FactorsABSTRACT
Two-dimensional echocardiography was used to study a consecutive series of 13 infants with persistent truncus arteriosus. In all a single great artery with the long upward course characteristic of the aorta was shown. This great artery could be identified as a persistent truncus arteriosus by the recognition of a branch arising from its ascending part (10 out of 13) or of more than three semilunar valve cusps (5/13). These criteria allowed the correct diagnosis to be reached in 12 of the 13 infants.
Subject(s)
Echocardiography/methods , Truncus Arteriosus, Persistent/diagnosis , Diagnosis, Differential , Humans , Infant , Infant, NewbornSubject(s)
Aorta , Echocardiography , Pulmonary Artery , Transposition of Great Vessels/diagnosis , Humans , InfantABSTRACT
No completely reliable echocardiographic technique has been described for the separate identification of the aorta and main pulmonary artery in complete transposition of the great arteries. A mechanical wide-angle (60 degrees) sector scanner has been applied to this problem in 17 infants and young children, including 8 newborns before angiocardiography. In all patients a longitudinal scan (saggital section) identified the main pulmonary artery by its directly posterior course immediately beyond the pulmonary valve, and the aorta by its retrosternal course upwards before turning posteriorly above the main pulmonary artery. In addition, a high transverse scan showed the precise spatial relation of the great arteries, and, in 11 of the 17, tilting the scanning plane upwards showed branching of the main pulmonary artery. In 8 infants examined with M-mode echocardiography, an upward sweep from the pulmonary valve showed abrupt termination of the echo from the posterior wall coinciding with the posterior arching of the main pulmonary artery.
Subject(s)
Transposition of Great Vessels/diagnosis , Aorta, Thoracic , Echocardiography , Humans , Infant , Infant, Newborn , Pulmonary ArteryABSTRACT
A wide angle (60 degrees) sector scanner producing a real-time two-dimensional echocardiogram has been used to examine healthy infants, children, and adults. Its method of use is described and findings from longitudinal and transverse scans are presented. The points of difference between the various types of electronic and mechanical two-dimensional scanning systems are discussed. This equipment minimises problems of chest contact and rib and lung interference and, by providing echocardiograms of high line density from a wide angle, is a suitable real-time two-dimensional scanning system for examining patients of all ages.
Subject(s)
Echocardiography/instrumentation , Adult , Child , Heart/anatomy & histology , Humans , Infant , MethodsABSTRACT
A delayed auditory feedback system has been constructed using solid state integrated circuit components. The construction of the instrument is described and the advantages of such an electronic device over conventional electro-mechanical systems are discussed.
Subject(s)
Auditory Perception , Speech Therapy/instrumentation , Speech , Analog-Digital Conversion , Electronics, Medical/instrumentation , Humans , Scotland , Stuttering/therapyABSTRACT
The technical details of a real time 2-dimensional ultrasonic scanning system are described, with particular regard to the improved clinical performance over other 2-dimensional scanners. Our instrument is capable of being used with existing ultrasonic equipment extending certain standard ultrasonic machines for use as real time 2-dimensional scanners conveniently and at little cost. Initial results are given and future technical developments are discussed.
